Constructing heterostructures of ZIF-67 derived C, N doped Co2P and Ti2VC2Tx MXene for enhanced OER

Abstract

Oxygen evolution reaction (OER) is central to technologies such as electrochemical water splitting, and developing efficient and low-cost non-precious metal electrocatalysts for OER is of great significance to reducing cell voltage and developing hydrogen production by electrochemical water splitting. Herein, we prepared a carbon, nitrogen co-doped porous Co2P derived from the metal-organic framework (ZIF-67), which is anchored on bimetallic MXene nanosheets (named MX@MOF-Co2P). It was used as the OER catalyst and exhibited great electrocatalytic performance with very small overpotentials (246 mV at 10 mA–2 and 407 mV at 200 mA cm–2) as well as ultralow Tafel slope (28.18 mV dec–1). Combining characterizations and theoretical calculations, it was found that the remarkable performance was from follows: the obtained MX@MOF-Co2P inherited the porous structure of the pristine MOF with a large number of open active sites; carbon and nitrogen doping also modulated the electronic structure of the active center; the synergistic effect between cobalt phosphide and MXenes booted the electronic transfer. This work represents a promising strategy for the development of non-precious metal catalysts derived from metal-organic frameworks to achieve efficient energy conversion.